6,358 research outputs found
The Variable-Order Fractional Calculus of Variations
This book intends to deepen the study of the fractional calculus, giving
special emphasis to variable-order operators. It is organized in two parts, as
follows. In the first part, we review the basic concepts of fractional calculus
(Chapter 1) and of the fractional calculus of variations (Chapter 2). In
Chapter 1, we start with a brief overview about fractional calculus and an
introduction to the theory of some special functions in fractional calculus.
Then, we recall several fractional operators (integrals and derivatives)
definitions and some properties of the considered fractional derivatives and
integrals are introduced. In the end of this chapter, we review integration by
parts formulas for different operators. Chapter 2 presents a short introduction
to the classical calculus of variations and review different variational
problems, like the isoperimetric problems or problems with variable endpoints.
In the end of this chapter, we introduce the theory of the fractional calculus
of variations and some fractional variational problems with variable-order. In
the second part, we systematize some new recent results on variable-order
fractional calculus of (Tavares, Almeida and Torres, 2015, 2016, 2017, 2018).
In Chapter 3, considering three types of fractional Caputo derivatives of
variable-order, we present new approximation formulas for those fractional
derivatives and prove upper bound formulas for the errors. In Chapter 4, we
introduce the combined Caputo fractional derivative of variable-order and
corresponding higher-order operators. Some properties are also given. Then, we
prove fractional Euler-Lagrange equations for several types of fractional
problems of the calculus of variations, with or without constraints.Comment: The final authenticated version of this preprint is available online
as a SpringerBrief in Applied Sciences and Technology at
[https://doi.org/10.1007/978-3-319-94006-9]. In this version some typos,
detected by the authors while reading the galley proofs, were corrected,
SpringerBriefs in Applied Sciences and Technology, Springer, Cham, 201
Diffusion-limited deposition with dipolar interactions: fractal dimension and multifractal structure
Computer simulations are used to generate two-dimensional diffusion-limited
deposits of dipoles. The structure of these deposits is analyzed by measuring
some global quantities: the density of the deposit and the lateral correlation
function at a given height, the mean height of the upper surface for a given
number of deposited particles and the interfacial width at a given height.
Evidences are given that the fractal dimension of the deposits remains constant
as the deposition proceeds, independently of the dipolar strength. These same
deposits are used to obtain the growth probability measure through Monte Carlo
techniques. It is found that the distribution of growth probabilities obeys
multifractal scaling, i.e. it can be analyzed in terms of its
multifractal spectrum. For low dipolar strengths, the spectrum is
similar to that of diffusion-limited aggregation. Our results suggest that for
increasing dipolar strength both the minimal local growth exponent
and the information dimension decrease, while the fractal
dimension remains the same.Comment: 10 pages, 7 figure
Diffusion-limited deposition of dipolar particles
Deposits of dipolar particles are investigated by means of extensive Monte
Carlo simulations. We found that the effect of the interactions is described by
an initial, non-universal, scaling regime characterized by orientationally
ordered deposits. In the dipolar regime, the order and geometry of the clusters
depend on the strength of the interactions and the magnetic properties are
tunable by controlling the growth conditions. At later stages, the growth is
dominated by thermal effects and the diffusion-limited universal regime
obtains, at finite temperatures. At low temperatures the crossover size
increases exponentially as T decreases and at T=0 only the dipolar regime is
observed.Comment: 5 pages, 4 figure
Synthesis of an antibody-like material for the detection of Albumin
6th Graduate Student Symposium on Molecular Imprinting6th Graduate Student Symposium on Molecular Imprinting, Medway School of Pharmacy, Kent, 27-28 de Agosto 2015A novel molecularly imprinted polymer (MIP) is presented for the detection of Albumin,
currently a biomarker of several diseases. The material acted as an antibody for Albumin and
was obtained through a bulk imprinting approach, by electropolymerizing Eriochrome blackT
(EBT) around the target protein
Concentração letal (CL50) do óleo essencial de mentha piperita (lamiaceae) em pirarucus arapaima gigas.
Na piscicultura, diversos produtos fitoterápicos vêm sendo usados no tratamento das parasitoses, principalmente causadas por helmintos. Mentha piperita, planta usada na medicina popular para tratar nauseas, vômitos, indigestão, desordens estomacais, cólicas mestruais e verminoses não tem sido testada em peixes, incluindo pirarucu Arapaima gigas. Porém, é importante conhecer a toxicidade de qualquer produto antes de recomendar a sua concentração terapêutica. Este ensaio realizado no Laboratório de Sanidade de Organismos Aquáticos da Embrapa Amapá, Macapá (AP), teve como objetivo determinar a concentração letal média (CL50-4h) do óleo essencial (OE) de M. piperita para pirarucus. Neste ensaio de toxicidade utilizou-se 168 alevinos de pirarucu (34,7 ± 12,4 g e 16,8 ± 2,0 cm) que após aclimatação foram distribuídos aleatoriamente em 14 tanques com volume para 80 L de água e na densidade de 12 peixes/tanque. O delineamento experimental foi inteiramente casualizado, constituído por dois grupos controles (um somente água do cultivo e outro água do cultivo contendo 80 ?L de álcool etílico absoluto) e seis concentrações (20, 40, 80, 100, 130 e 160 mg/L) de OE de M. piperita em duplicatas. As concentrações do OE foram diluídas em álcool etílico (1g:10 mL). Durante o período de 4 horas de exposição ao OE, os peixes foram mantidos sem alimentação, em sistema estático de água e a CL50-4h, foi calculada usando o método de Trimmed Spearman-Karber. Os resultados mostraram que a CL50-4h de M. piperita foi 38 mg/L, com intervalo de confiança (95%) variando de 30-40 mg/L. Portanto, o teste de toxicidade aguda indica que as concentrações clínicas para banhos terapêuticos de pirarucus com OE de M. piperita devem ser abaixo desses valores obtidos, para evitar mortalidade dos peixes, que é indesejada em qualquer piscicultura durante o tratamento antiparasitário.US100
Ecologia parasitária de Metynnis lippincottianus Cope, 1870 (Serrasalmidae) na Amazônia Oriental, Estado do Amapá, Brasil.
PAR05
A novel printed 3-electrode system for the electrochemical detection of sulfadiazine
We thank the financial support of 3C´s – Cellulose and Cork in the Control of antibiotics in
aquaculture (PTDC/AAG-TEC/5400/2014 and POCI-01-0145-FEDER-016637), to FEDER, through COMPETE2020,
POCI, and FCT (Fundação para a Ciência e a Tecnologia I.P.).info:eu-repo/semantics/publishedVersio
Primeiro estudo sobre protozoários e metazoários parasitando Hemibrycon surinamesis (Characidae).
PAR052
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